Individuals who are visually impaired face many obstacles to everyday navigation. For example, such individuals often must use public transportation, such as a subway system, for travel. Those systems may be difficult to navigate without the benefit of adequate sight, and thus it is desirable to provide a guidance system that is inexpensive, reliable, and durable.
One type of conventional guidance system includes a longitudinally extensive, permanently magnetized region, such that a sensor mounted in a cane can emit a sound when the cane is swept across the region. Although these systems have utility, one disadvantage is that they can be unipolar, meaning that they have only one polarity and can emit only one signal as the cane sweeps over the magnetic field. Also, conventional systems that are not based on permanent magnets typically require comparatively expensive sensors to detect the signal.
Another disadvantage of several conventional guidance systems is that they cannot be easily applied to an existing surface. Some systems include, for example, magnets embedded in a surface to activate a sensor. This arrangement is inconvenient to install in an existing surface, because the surface may have to be at least partially destroyed to embed the magnet. Also, if the magnets are permanently adhered to or embedded within the surface, they cannot easily be repositioned to indicate a new pathway.
Yet another disadvantage of some conventional guidance systems is that they may not provide the most effective guidance for sighted, but visually-impaired, individuals. That is, systems designed to aid persons who are completely blind may not have other useful attributes that would aid a sighted, but visually-impaired person. In view of these and other disadvantages associated with conventional guidance systems, it is desirable to provide a new guidance system having a variety of available features.